package com.taobao.zeus.util;
  
import java.beans.IntrospectionException;  
import java.beans.Introspector;  
import java.beans.PropertyDescriptor;  
import java.math.BigDecimal;  
import java.math.BigInteger;  
import java.util.ArrayList;  
import java.util.List;  
import java.util.Map;  
import java.util.Set;  
import org.apache.commons.logging.Log;  
import org.apache.commons.logging.LogFactory;  
  
public class JsonUtil {  
    private static Log log = LogFactory.getLog(JsonUtil.class);  
    public static String object2json(Object obj) {  
        StringBuilder json = new StringBuilder();  
        if (obj == null) {  
            json.append("\"\"");  
        } else if (obj instanceof String || obj instanceof Integer || obj instanceof Float || obj instanceof Boolean || obj instanceof Short || obj instanceof Double || obj instanceof Long || obj instanceof BigDecimal || obj instanceof BigInteger || obj instanceof Byte) {  
            json.append("\"").append(string2json(obj.toString())).append("\"");  
        } else if (obj instanceof Object[]) {  
            json.append(array2json((Object[]) obj));  
        } else if (obj instanceof List) {  
            json.append(list2json((List<?>) obj));  
        } else if (obj instanceof Map) {  
            json.append(map2json((Map<?, ?>) obj));  
        } else if (obj instanceof Set) {  
            json.append(set2json((Set<?>) obj));  
        } else {  
            json.append(bean2json(obj));  
        }  
        return json.toString();  
    }  
    public static String bean2json(Object bean) {  
        StringBuilder json = new StringBuilder();  
        json.append("{");  
        PropertyDescriptor[] props = null;  
        try {  
            props = Introspector.getBeanInfo(bean.getClass(), Object.class).getPropertyDescriptors();  
        } catch (IntrospectionException e) {  
        }  
        if (props != null) {  
            for (int i = 0; i < props.length; i++) {  
                try {  
                    String name = object2json(props[i].getName());  
                    String value = object2json(props[i].getReadMethod().invoke(bean));  
                    json.append(name);  
                    json.append(":");  
                    json.append(value);  
                    json.append(",");  
                } catch (Exception e) {  
                }  
            }  
            json.setCharAt(json.length() - 1, '}');  
        } else {  
            json.append("}");  
        }  
        return json.toString();  
    }  
    public static String list2json(List<?> list) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (list != null && list.size() > 0) {  
            for (Object obj : list) {  
                json.append(object2json(obj));  
                json.append(",");  
            }  
            json.setCharAt(json.length() - 1, ']');  
        } else {  
            json.append("]");  
        }  
        return json.toString();  
    }  
    public static String array2json(Object[] array) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (array != null && array.length > 0) {  
            for (Object obj : array) {  
                json.append(object2json(obj));  
                json.append(",");  
            }  
            json.setCharAt(json.length() - 1, ']');  
        } else {  
            json.append("]");  
        }  
        return json.toString();  
    }  
    public static String map2json(Map<?, ?> map) {  
        StringBuilder json = new StringBuilder();  
        json.append("{");  
        if (map != null && map.size() > 0) {  
            for (Object key : map.keySet()) {  
                json.append(object2json(key));  
                json.append(":");  
                json.append(object2json(map.get(key)));  
                json.append(",");  
            }  
            json.setCharAt(json.length() - 1, '}');  
        } else {  
            json.append("}");  
        }  
        return json.toString();  
    }  
    public static String set2json(Set<?> set) {  
        StringBuilder json = new StringBuilder();  
        json.append("[");  
        if (set != null && set.size() > 0) {  
            for (Object obj : set) {  
                json.append(object2json(obj));  
                json.append(",");  
            }  
            json.setCharAt(json.length() - 1, ']');  
        } else {  
            json.append("]");  
        }  
        return json.toString();  
    }  
    public static String string2json(String s) {  
        if (s == null)  
            return "";  
        StringBuilder sb = new StringBuilder();  
        for (int i = 0; i < s.length(); i++) {  
            char ch = s.charAt(i);  
            switch (ch) {  
                case '"' :  
                    sb.append("\\\"");  
                    break;  
                case '\\' :  
                    sb.append("\\\\");  
                    break;  
                case '\b' :  
                    sb.append("\\b");  
                    break;  
                case '\f' :  
                    sb.append("\\f");  
                    break;  
                case '\n' :  
                    sb.append("\\n");  
                    break;  
                case '\r' :  
                    sb.append("\\r");  
                    break;  
                case '\t' :  
                    sb.append("\\t");  
                    break;  
                case '/' :  
                    sb.append("\\/");  
                    break;  
                default :  
                    if (ch >= '\u0000' && ch <= '\u001F') {  
                        String ss = Integer.toHexString(ch);  
                        sb.append("\\u");  
                        for (int k = 0; k < 4 - ss.length(); k++) {  
                            sb.append('0');  
                        }  
                        sb.append(ss.toUpperCase());  
                    } else {  
                        sb.append(ch);  
                    }  
            }  
        }  
        return sb.toString();  
    }  
    
    public static void main(String args[]) {  

    }  
}  